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प्रश्न
State the mathematical relation between a number of turns in the primary coil to a secondary coil in the step-up transformer.
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उत्तर
In a step-up transformer, the number of turns in the secondary coil is more than that in the primary coil (NS > NP).
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संबंधित प्रश्न
Derive an expression for ratio of e.m.f.s and currents in terms of number of turns in primary and secondary coil.
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(c) a voltage across secondary
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(e) power in secondary
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Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
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Read the following paragraph and answer the question:
Long distance power transmissions
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In an ideal transformer, the turns ratio is `N_p/N_s = 1/2`. The ratio Vs : Vp is equal to (the symbols carry their usual meaning):
